The HPGR technology has been identified as the most attractive grinding option, given the data obtained from the comminution testwork conducted in 2009 and in 2017–2018.
During 2020, representative samples from different lithologies of the mine plan were sent to a laboratory in USA for pressure bed testing, confirming the amenability of Vizcachitas mineralized material for processing with HPGR
HPGR benefits the Vizcachitas project by:
- Improving the operational flexibility by reducing sensitivity to hardness variability and produce a more stable particle size distribution, minimizing major process fluctuations in the downstream process.
- Lower operating costs based due to lower energy consumption and lower grinding media consumption.
- Reducing maintenance times (from 90 to 24 hours) when compared with the usual semi-autogenous grinding (SAG) alternative.
Vizcachitas novel approach to the crushing circuit considers three secondary crushers operating in open circuit with enough power and capacity to produce an amenable product to be fed to the HPGRs. This removes the recirculation of the secondary stage; reducing dust emissions, minimizing the facilities footprint and reducing CAPEX/OPEX of the conveyor belts.
Vendor-based simulations and the Companies calculations defined the perform preliminary sizing and selection of equipment. This testwork will be confirmed with a pilot plant during the feasibility stage.